1. Field of the Invention
The present invention relates to a sensor for detecting a crash that is typically used for an air bag that is for protecting a passenger during an automobile accident particularly at the side of the automobile.
2. Background of the Invention
A system has recently been proposed which, in addition to a seat belt device, is provided with an air back device for the protection of a passenger during an accident. The conventional air bag device is mainly directed to the protection of a passenger upon a head-on collision, wherein it is provided with an air bag arranged in the steering wheel column or instrumental panel in front of the driver or passenger which, upon the occurrence of an accident the air bag inflates and occupies a space to cushioning the person therein.
In addition to the above mentioned usual type of air bag for the protection of a passenger during a head on collision, another type of air bag device has been proposed for the protection of a passenger during impact from the side of the vehicle, wherein the air bag device is usually stored in a side door or side wall of the vehicle body. During an accident, an air bag stored in the side door or side wall is inflated so that it occupies the space between the passenger and the side door or wall for protection thereat. In order to detect the occurrence of a lateral impact a sensor in the vehicle that responds to said impact is provided.
However, the prior art crash sensor is ineffective at high speed and cannot accurately detect lateral impact. Consequently there is a demand for a sensor capable of attaining the above function.